(a) Field of the Invention
The present invention relates to a closure assembly for a container, in particular to a closure assembly which is child resistant and which is especially adaptable for use with a tamper evident closure arrangement and/or to a closure assembly including a new tamper evident closure arrangement.
(b) Description of the Prior Art
A variety of child resistant closures are known in the art. Such closures rely on features designed to make opening difficult for a child while at the same time (in theory at least) permitting relatively easy access by a more knowledgeable adult. Thus, in one widely used closure arrangement it is necessary to line up two arrows before opening can be effected, and in another widely used arrangement for screw caps the cap must be pressed down while unscrewing, otherwise it rotates freely without opening the closure.
As other examples there may be cited the closures disclosed in British Specifications Nos. 1,442,216 and 2,166,423. In the former there is disclosed a child resistant closure assembly for a container, shaped to give the appearance of a conventional screw cap with longitudinal flutes, serrations, ribs or ridges on its outer surface. The assembly comprises a facsimile cap and a snap on lid adapted both to open and to close an opening in the top of the facsimile cap and to be retained in its closed position to give an integral appearance to the top of the closure assembly. The facsimile cap has a portion of its outer surface which is displaceable inwardly to allow a finger of a user to engage under the snap on lid to overcome the snap action of the lid, the displaceable portion being a portion that is not readily distinguishable from the remainder of the facsimile cap. The child resistant feature of the cap resides in the idea of designing a cap to deceive the uninformed user to attempt to open it in a particular manner i.e. by unscrewing the cap, when in fact the cap is openable in another manner i.e. by flipping open a snap on lid - a fact readily conveyed to the informed (adult) user.
In the latter there is disclosed a two part child resistant closure, which comprises a top cap hingedly connected to an inner cap which is adapted to be semipermanently positioned over the mouth of an associated container. On the inner cap there is a depending skirt and a trigger forming part of the skirt, actuation of the trigger normally being prevented by engagement of the trigger with an arcuate bead on the outside of the associated container whereby the trigger forms a locking means to hold the top cap in its closed position until the closure is angularly displaced relatively to the container into a predetermined position. In that position the trigger on the inner cap can be depressed to disengage the trigger from locking engagement with the top cap.
At present it is well appreciated in the art that child resistant closures can save life. The use of known closures has shown that child safety is considerably improved once a child resistant feature is included in a closure. However, while known, and well tested and approved, child resistant closures have demonstrated the success of the concept, there remains generally a concern that one or both of the degree of child resistance and the ease of use by the elderly could be enhanced.
Thus, for example, with the closure where arrows must be aligned before opening, such alignment can be difficult for the elderly. Also, with the elderly especially, there is a tendency to replace the lid or cap with the arrows aligned for ease of opening next time, but that immediately eliminates the safety feature. Furthermore, the elderly often lack the strength or manual control to press down that closure which requires to be pressed down as it is unscrewed before it will open. Also again, once they have opened such a closure they will often not close it sufficiently to bring the safety feature into operation, thus negating the feature.
Accordingly, there remains in the art a need for a child resistant closure which can be understood by the adult, which is manageable by the elderly, and which when closed (however that may be effected) always includes an operating child resistant feature. That is to say the child resistant feature should operate on closure irrespective of any subsequent twisting or tightening of the lid or cap.
Furthermore, there remains in the art a need for a child resistant closure which can afford an acceptable level of child resistance while at the same time being adaptable for use with a tamper evident closure arrangement.